Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Force of attraction and repulsion equal?

Force of attraction and repulsion equal?

Force of attraction and repulsion equal?

I've been doing some searching and I've found some information that seems to suggest that magnets exert a slightly higher attractive force than their repulsive force, when dealing with two identical magnets.  For example, two magnets placed N to S would exert more force on each other (attractive) than the same magnets placed N to N or S to S (repulsive) at the same distance of separation.  The difference is supposedly very slight, and decreasing as distance increase.  Can anyone confirm this?  

Here is the link to the information:

I'm new to studying magnets, so please forgive my lack of knowledge on this subject.

RE: Force of attraction and repulsion equal?

It is completely obvious that attractive and repulsive forces as you state them are not equal. Those forces may be interpreted as a result of change of magnetic energy stored in the system when the distance between the magnets changes by an infinitesimal quantity. Now the magnetic energy is related to the pattern of the induction flow, and this is different, not simply symmetrical, when polarities oppose or concur.

http://www.xcalcs.com : Online tools for structural design
http://www.megamag.it : Magnetic brakes for fun rides
http://www.levitans.com : Air bearing pads

RE: Force of attraction and repulsion equal?

Since the flux distribution are different I would expect the forces to be different.  The difference should also depend on the size/shape of the magnets.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

RE: Force of attraction and repulsion equal?

Thank you for your replies.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close